<template>
  <el-menu
    default-active="2"
    class="el-menu-vertical-demo"
    id="leftMenu"
    @open="handleOpen"
    @close="handleClose"
  >
    <el-submenu index="1">
      <template slot="title">
        <i class="el-icon-location"></i>
        <span>导航一</span>
      </template>
      <el-menu-item-group>
        <template slot="title">分组一</template>
        <el-menu-item index="1-1">选项1</el-menu-item>
        <el-menu-item index="1-2">选项2</el-menu-item>
      </el-menu-item-group>
      <el-menu-item-group title="分组2">
        <el-menu-item index="1-3">选项3</el-menu-item>
      </el-menu-item-group>
      <el-submenu index="1-4">
        <template slot="title">选项4</template>
        <el-menu-item index="1-4-1">选项1</el-menu-item>
      </el-submenu>
    </el-submenu>
    <el-menu-item index="2">
      <i class="el-icon-menu"></i>
      <span slot="title">导航二</span>
    </el-menu-item>
    <el-menu-item index="3" disabled>
      <i class="el-icon-document"></i>
      <span slot="title">导航三</span>
    </el-menu-item>
    <el-menu-item index="4">
      <i class="el-icon-setting"></i>
      <span slot="title">导航四</span>
    </el-menu-item>
  </el-menu>
</template>
<script>
export default {
  name: "leftMenu",
  methods: {
    handleOpen(key, keyPath) {
      console.log(key, keyPath);
    },
    handleClose(key, keyPath) {
      console.log(key, keyPath);
    }
  },
  mounted: function() {
    let windowH = document.documentElement.clientHeight;
    document.getElementById("leftMenu").style.height = windowH - 60 + "px";
  }
};
</script>
<style scoped>
.el-menu-item,
.el-submenu__title {
  height: 48px;
  line-height: 48px;
}
</style>